Dr. Vasi (Rajnikanth) invents a super-powered robot, Chitti, in his own image. The scientific body, AIRD, that must approve the robot, declines it based on its not having emotions and the ability to make rational judgment. A sudden flash of lightning evokes emotions in the robot, and Chitti is seemingly ready for integration into the human world. Then, Chitti falls in love with Dr. Vasi's fiancée Sana (Aishwarya Rai) and turns on his creator.

Circa the British rule in India, a man named Senapathy decides to rebel against the British in a violent way, learns a rare martial art that enables him to kill with his bare hands, and travels to Singapore, joins the Indian Liberation Army formed by renowned Subhash Chandra Bose, is one of the soldier's to engage the British into war. He subsequently joins a death squad in order to destroy British tanks. While all of the others succeed in carrying out their mission, Senapathy is captured, jailed, beaten, and mercilessly tortured by the British. Upon his release, he is looked after by a woman named Namrata, whose honor he had saved from the British - who had captured two truckloads of women protesters, burned their clothing, and forced them to commit suicide. Namrata and Senapathy marry, India gains independence, and they soon have two children - Chandrabose and Kasthoori. Years later Chandra quarrels with his honest and straight-laced father...

Held in a cell, Sivaji reflects how he came to be under police scrutiny and his subsequent arrest for a variety of economic offenses. He had returned to Chennai from the U.S. to live with his parents and maternal uncle, and had hoped to invest money in colleges and hospitals so that people who are not privileged can benefit - much to the chagrin of a sophisticated goon, Adisheshan, who threatens him, and asks him not to tread on his territory. Disregarding this and hoping to get his projects going, Sivaji runs into bureaucratic corruption and red-tape - so much so that he gives in and bribes an official Rs.4 Crores to complete his Rs.200 Crore project. An enraged Adisheshan has the local politician stop the work, but Sivaji bribes the latter Rs.50 Crores, after liquefying most of his assets. While he is busy wooing and attempting to marry Tamizhselvi/Vidyabharti Ramlingam, a new politician takes over...